I had gastric bypass & was pulled over for speeding but arrested for DUI when I was not drunk. Can I use this as a defense?

I was driving home from work from a night club crying after being harassed & threatened by a fellow employee. At work I had 1 miller lt. beer, a glass of water, then a glass of plain cranberry juice & an additional 1/4 glass of water before leaving to go home. I was not impaired and had no effects from the alcohol. I was upset & crying when I was pulled over for speeding. I admitted my guilt for speeding and told the deputy what had happened. Because my eyes were "red" he wanted to know if I was smoking anything. When I said no he asked if I had been drinking and I said, I had 1 beer.I did 2 field sobriety tests which I passed then a breath test which I was sure I would pass but came up .08 then .09 @ station. I had gastric bypass & I'm sure that's why my BAC came up so high w/just 1 beer.